SKIP TO 1:15 FOR DIRECT INFORMATION ABOUT ANALOG AND DIGITAL SIGNALS
|
The most important EM radiation that connects to analog and digital are radio, microwave, infrared and visible radiation. As mentioned they are used for communication. These four types of radiation are harmless and currently show no sign of causing any illnesses or mutations in humans compared to ultraviolet, x ray and gamma ray radiation.
There are two types of signals: analog and digital. These both have their beneficial qualities, and could almost regard them as opposites. Analog signals continiously change, whilst digital signals have a restricted scale (for example being binary formatted.) The video on the left explains the basics about analog and digital signals. |
First four types of EMS radiation
Radio radiationA direct electrical current is applied to a wire, the current flow builds an electromagnetic field around the wire. The field sends a wave outward from the wire. When the current is removed, the field collapses, which then sends another wave.
They are used for tv and radio signal transmission for short and long distances. InfraredInvisible to the human eye, and is emitted by all objects and is sensed by heat. The larger amount of infrared emitted, the more hotter the object is.
|
MicrowaveMicrowaves are produced by vacuum tube devices that operate on the gravitational motion of electrons. It is controlled by magnetic or electric fields.
They are used for transmitting information through satellites, as they can easily pass through the ionosphere. Visible lightWhen an atom's electron becomes energised, the electrons move away from the nucleus, at the same time emits the energy as light
Both infrared and visible light radiation are sent through by optical fibres. |